Float & Thermostatic Steam Traps
F&Ts contain a float-operated valve to continually discharge condensate and a thermostatic air vent which discharges air. Body materials available are Cast Iron, Ductile Iron, Cast Steel, & Stainless Steel for pressure up to 450 psig. F&Ts are the most commonly used trap for the majority of process applications. These traps are also suitable for drip applications on pressures 30 psig & below.
- F&Ts quickly respond to load and pressure changes
- Discharge large amounts of air present at start-up which allow steam to quickly enter the system.
| Model | Characteristics | Material | Application | |
|---|---|---|---|---|
| WFT |  | Parallel Pipe Connection | Cast Iron | Primary Selection forLow to Medium Capacity Smaller sizes can also be used forDrip Applications |
| FTT FTTS |  | In-Line PipeConnection | FTT: Ductile Iron FTTS: Stainless Steel | |
| FTE |  | High-Capacity | FTE: Ductile Iron FTES:Cast Steel | High Capacity Process Applications |
| FT600 |  | In-LinePipe Connection | FT600:Carbon Steel FT601:Stainless Steel | Higher Pressure Application |
| FT |  | Parallel Pipe Connection(H-pattern) | Cast Iron | Primary Selection forLow to Medium Capacity Smaller sizes can also be used forDrip Applications |
Float & Thermostatic Applications
F&T steam traps are the most common trap type used for process applications. They use a float-operated valve mechanism to discharge condensateas it is formed, and an air vent for discharging air at start-up; both very important requirements for process applications.
The WFT and FTT-Series with Iron bodies, are suitable for most general purpose process applications.
The FTE-Series are used for extremely high capacity applications.
The FT600 Series with Cast Steel bodies; are capable of higher pressures and often required in Chemical and Petrochemical refineries and otherindustries.
Process Application for Float & Thermostatic Traps
Jacketed Kettle
As the name implies, Jacketed Kettles have a Jacket of Steam surrounding theoutside of a Kettle. They are commonly used in the food and beverage industry forindirect heating of the contents in the kettle. F&T traps are the most commonlyused trap on process applications due to their high condensate handling abilityand superior air handling during start-up. This application demonstrates the useof the FTT model Float and Thermostatic steam trap with in-line pipe connections.
Shell & Tube Heat Exchanger
Shell & Tube heat exchangers are used for continuous processes such asheating a continuous flow of water or other liquid. F&T traps quickly respond torapidly changing loads and pressures common to this application. They alsodischarge large amounts of air present at start up which allows steam to quicklyenter the system.
Multi-Bank Air Heating Coils/ Air Handling Unit (AHU)
For certain Industrial Heating and Drying applications, several Air Heating coils of various sizes may be set up in series to accommodate the process. Theheat load of each coil should be taken into account when sizing the steam traps. It’s preferable to have a separate steam trap on each individual coil.
Rotating Steam Dryer
Commonly found in the Paper Making industry, a rotating piece of equipmentoffers a unique challenge of removing the condensate. Steam inside a rotatingdrum cylinder is used to heat product such as sheets of paper over the outsidesurface of the drum. Since the drum is rotating, the trap must be positioned abovethe condensate collection point. The steam pressure inside the drum pushes thecondensate up through the pipe to the steam trap. If steam enters the tubing, itwill “Steam Lock” the trap by causing it to close which in turn causes thecondensate to build up inside the rotating drum. Since the pipe line is surroundedby steam, it may take an extended length of time for the steam in the pipe todissipate. By using the Steam Lock Release feature, a small amount of steam iscontinually discharged thru the seat, allowing the condensate to continually reachthe steam trap. This steam lock release feature is available on ALL F&T andThermostatic traps and should be considered on this type of application.
Instantaneous Steam to HotWater Heater (Heat Miser)
Pre-packaged water heating systems such as the Heat Miser are popular choicesfor heating domestic water with steam. They can be designed to handle widevariations in flow demand, depending on how much hot water is needed at aparticular time of day. Float & thermostatic steam traps are the primary selectionfor these and similar water heating packages based on their ability to adjust towide variations in flow rate, as well as their ability to discharge air for fast start-up.
Drip Application for Float & Thermostatic Traps
Steam Main Drip Application
The Float & Thermostatic (F&T) Steam Trap is the primary choice for processapplications. However, for drip applications, they can be effectively used forpressures up to 125 psig on the WFT Series & 225 psig on the FTT Series; forhigher pressures, the larger body sizes required make F&T traps a less economicaland desirable solution for drip service. The 3/4" WFT-125, or 1/2" & 3/4" FTT-225will meet the capacity needs of most drip applications. Other PMO (maximumoperating pressure) ranges available. For drip applications, select a PMO thatmeets or exceeds the maximum pressure in the main steam distribution piping.
Steam Separator
Separators are used on steam mains and steam supply lines to remove entrainedwater in the steam. Steam flows through the separator and the condensate fallsby gravity to the bottom where it needs to be discharged through a steam trap.F&T traps are recommended for this application.
Float & Thermostatic Traps
F&T steam traps are the most common trap type used for process applications. They use a float-operated valve mechanism to discharge condensate as it is formed, andan air vent for discharging air at start-up; both very important requirements for process applications.
Venting Air
Prior to the steam being turn on the piping system, heat exchanger andtrap are filled with air which is much cooler than steam. The thermostaticair vent will be in the wide open position. During startup this air will bepushed through the air vent by the incoming steam into the condensatereturn line.
Discharging Condensate
When condensate enters the trap, the float lifts which opens the valve,allowing condensate to discharge.
Closed (Trapping Steam)
When steam is present, and no condensate is entering the trap, the valveand thermostatic air vent remain closed, trapping steam in the system.
